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<div class="titlepage"><div><div><h4 class="title">
<a name="phoenix.lazy_list.tutorial_with_examples.list_generation"></a><a class="link" href="list_generation.html" title="List Generation">List
        Generation</a>
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<p>
          One of the most interesting capabilities of <a href="http://cgi.di.uoa.gr/~smaragd/fc++/" target="_top">FC++</a>
          is the generation of infinite lazy lists which are evaluated only at need.
          The most simple example of this is
        </p>
<pre class="programlisting"><span class="identifier">enum_from</span><span class="special">(</span><span class="number">1</span><span class="special">)</span>
</pre>
<p>
          which returns the generator for integers 1,2,3,..... infinity.
        </p>
<pre class="programlisting"><span class="identifier">take</span><span class="special">(</span><span class="number">4</span><span class="special">,</span><span class="identifier">enum_from</span><span class="special">(</span><span class="number">1</span><span class="special">))</span>
</pre>
<p>
          returns a list of the first 4 of the list.
        </p>
<pre class="programlisting"><span class="identifier">at</span><span class="special">(</span><span class="identifier">enum_from</span><span class="special">(</span><span class="number">1</span><span class="special">),</span><span class="number">3</span><span class="special">)</span>
</pre>
<p>
          returns the fourth member using zero indexed access. Both of the lists
          returned are lazy and only evaluated when the list members are accessed.
        </p>
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